Allow toString capability to be toggled independent of developer mode

include/core/SkTypes.h

Index: include/core/SkTypes.h
===================================================================
--- include/core/SkTypes.h	(revision 13782)
+++ include/core/SkTypes.h	(working copy)
@@ -115,14 +115,24 @@
 
 #ifdef SK_DEVELOPER
     #define SkDEVCODE(code)             code
-    // the 'toString' helper functions convert Sk* objects to human-readable
-    // form in developer mode
-    #define SK_DEVELOPER_TO_STRING()    virtual void toString(SkString* str) const SK_OVERRIDE;
 #else
     #define SkDEVCODE(code)
-    #define SK_DEVELOPER_TO_STRING()
 #endif
 
+#ifdef SK_IGNORE_TO_STRING
+    #define SK_TO_STRING_NONVIRT() 
+    #define SK_TO_STRING_VIRT() 
+    #define SK_TO_STRING_PUREVIRT()
+    #define SK_TO_STRING_OVERRIDE()
+#else
+    // the 'toString' helper functions convert Sk* objects to human-readable
+    // form in developer mode
+    #define SK_TO_STRING_NONVIRT() void toString(SkString* str) const;
+    #define SK_TO_STRING_VIRT() virtual void toString(SkString* str) const;
+    #define SK_TO_STRING_PUREVIRT() virtual void toString(SkString* str) const = 0;
+    #define SK_TO_STRING_OVERRIDE() virtual void toString(SkString* str) const SK_OVERRIDE;
+#endif
+
 template <bool>
 struct SkCompileAssert {
 };